Abstract

The growth of GaN and on -plane sapphire substrates was carried out by molecular beam epitaxy using In situreflection high-energy electron diffraction(RHEED) was used to monitor the growth process. Oscillations of the specular beam intensity were observed during both GaN and deposition. This allows determining in real time the composition of alloys. The effects of the growth temperature and the Ga flux on the In incorporation rate were investigated. The critical thickness for InGaN islanding as a function of In mole fraction is also easily deduced from RHEED experiments.